Transformer.



- No. 696,953. Patented Apr. 8, 1902 Am svznzsr.

TRANSFOBIER.

(Application filed In. 5. 1901.) (No Model.) 3 Sheets-Shoat l.

O-" fl 1 Q0- A I O g i Fig. 2. l

B {L c l i E i o i 0 E Fig.5. B 2 I O O t W t jnvenfort 1 messes. flugusflneREveresT,

mtj

Patented Apr. 8, I902. A. R. EVEREST.

TRANSFORMER.

(Application filed In. 5, 1901.)

3 Sheets-Sheet 3.

(lo lodal.)

Yeresl, Q'

Inuenoorr usiz' 126R. 5

witnesses:- ezgmf@%@ Tn: n'onms men 00,, momumo" wullmofoy. n. c.

UNITED STATES PATENT OFFICE.

AUGUSTINE R. EVEREST, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

TRANSFORM ER.

SPECIFICATION forming part of Letters Patent No. 696,953, dated April 8, 1902.

Application filed March 5, 1901. Serial No. 49,693. (No model.)

To alt whom it 72mg concern: reduced, and transformershavingcores made Be itknown that LAUGUsTlNE R. EVEREST, in this manner have been uniformly efficient a subject of the King of Great Britain, residin operation and economical in manufacture. ing at Lynn, county of Essex, State of Massa- It may be noted at this point that, as de- 55 chusetts, have invented certain new and usescribed in an application of W'alter A. Hall, fullmprovements in Transformers, (Case No. Serial No. l9,69i, filed of even date herewith, 1,723,) ofwhichthefollowingisaspecification. it has recently been discovered that the U- Thisinvention relates to new and useful imshaped laminze used in executing my invenprovements in the construction of laminated tion are susceptible of being produced in a 60 1o transformer-cores of the general type disvery economical manner. This of course is closed in the patent to Moody, No. 567,250. an additional advantageous feature of my in- As described in that patent the coils were first vontion. wound on two bundles of straightlaminzehav- Figure 1 is a plan of a sheet-metal blank ing tongue-and-groove ends, which bundles, upon which is performed the first or punch- 65 withthe coils woundthereon,werethen placed ing operation as constructed in accordance asuitable distanceapartandtheirendsjoined with the method invented by Hall. Fig. 2 by short bundles of laminae to complete the shows a short end lamina which is the result magnetic circuit. One end of each short bunof this operation. Fig. 3 is a plan which dle interlocked with the tongue-and-groove shows the result of a second or shearing and 70 end of the long bundle, which constituted one final operation, also as constructed in accordleg of the core. The other end of each short anee with the methodinvented byHall. Fig. bundle abutted against the side of the long 4. is a reversed plan of the blank shown in bundle, which constituted the other leg ofthe Fig. 1 before the punching operation has core. This proved a very cheap and conventaken place. Fig. 5includes views of the three 75 ient mode of constructing a durable andeffiparts which are punched or sheared from the cient transformer. However, there was a not blank shown in Fig. l. Fig. 6 is a perspective inconsiderable core loss in transformers conview showing the core in process of construestructed in the above manner, which was due tion from the parts shown in Fig. 5. Fig. '7is a to the fact that there were necessarily four perspective View showing the free ends of the 80 joints between the laminae. lVith the aid of assemblage of the sheared U-shaped lamina: and in accordance with the present invention and the location of the punched end sheets of transformers have been made which show a laminie which complete the magnetic circuit. reduction in core loss of over five per cent. Fig. 8 is an end View showing the method of with respect to transformers constructed as looking the end sheets in place; and Fig. 9 is 85 described above. This isavery conservative an elevation of the core complete, the coils estimate. As the core loss of a transformer having been slipped over the core-legs and continues independently of translating dethe end sheets having been inserted in posivices in the secondary circuit, it is clear that tion. such a reduction is material and important. W'ith reference to Fig. 1, the first or punch- 0 40 This result has been obtained by reducing ing operation, which is accomplished by a the number of joints between the laminae, so suitable die, trims away the edges XYof the thatabettermagnetic circuit is obtained. The sheet-metal blank A, punches the pin-holes core made in accordance with this invention H, and punches the holes E and F, leaving is built up of substantially U -shaped laminae, the strip M between them. The sheet of lami- 5 each of which has a long and short leg. The nae E (shown in Fig. 2) occupied the space coils are wound independently and are after- E and is cut out in this operation in order to ward slipped over the legs of the U-shaped save a separate operation of cutting it to core, which is left open at one end for this proper length later, the length shown in Fig. purpose. The number of joints between the 2 being its final length for adapting it to be I00 laminae can be decreased by this construction, used as an end sheet for the core. During so that the fixed. core loss willbe considerably the first operation also the guide G is cut in the upper portion of the blank A. The part M is left to hold the parts rigid until the second or shearing operation, when, as is clear, it can also be sheared off. The part F, which is wasted, is punched out in order to permit the second operation to be merely a shearing operation without the punching which would be necessary if the corners were not removed before the second operation. The removal of the part E by punching permits the shearing to be accomplished along the dotted line at the lower portion of Fig. 1. In any case there must be a free space at the beginning of the part to be sheared in order to permit the operation of the shear. The second or shearing operation results in the separation of the metal along the dotted lines in Fig. 1, the result of which is seen in Fig. 3, wherein the guide I of the lower right-hand corner is also formed. In the case shown the part M is wasted; but this is not always the case.

In Fig. 3 it will be seen that two substantially U-shaped laminae are formed, each having a which is equal to the difference between the length of the long leg and the width of the base of the U-shaped laminae, so that when the parts are arranged, as in Fig. 3, just as they come from the blank A they form a rectangular figure. In addition it will be observed in Fig. 3 that the space between the short inner legs 13 and G is of the same width as the legs or bases of the U- shaped laminae, or, in other words, the distance between the long leg and the short leg of one laminae is twice the width of either leg, and therefore equal to the added widths of both legs. From the metal in the space between the short legs 13 and C in Fig. 3 the end sheets of the core are always formed, and according to the dimensions of any given transformer there will be a greater or less waste. In the case illustrated the amount of metal wasted in the construction of this trans- 'A. Hall, and is more particularly described and claimed in his application for patent,

Serial No. 4.9, 694.

In Fig. 5 the three pieces formed from the blank are shown separately, and it should be particularly noted that the lamina O has the outside corner of its longer leg 0 cut away at I, while the lamina B has the innercorner of the end of its long leg B cut away at G. In Fig. 6 is shown a partial assemblage of these parts held together by wooden pins W,

which fit tightly in the holes H. The ends E are not inserted until the coils have been slipped over the core-legs. In assembling the laminae are slipped loosely over pointed steel pins. The steel pins are then removed and the wooden pins are driven into the holes. The coils L of Fig. 9,which have been wound by another operation, are then (Fig. 9) slipped over the legs of the core and the end sheets E are inserted, as shown-in Fig. 7. In the latter figure the lower portion of the core, which is integral with the legs, is cut away. It will be observed that each end sheet E is inserted between the projecting ends of the longer legs, according to the indication afforded by I the guides G and I. The guide I on the righthand corner of the end of the right-hand long leg and the guide G on the left-hand corner of the end of the long leg behind the first serve to indicate to the operator that the end sheet E'is to be placed in the space between them. The other end of the end sheet abuts against the side of the end of the long leg, which is contained in the left-hand leg of the core. The end of the next end sheet is inserted between the projecting ends of the long legs of the left-hand core-leg, as indicated to the operator by the guides I and G, and this end sheet abuts against the inner side of the end of the opposite long leg of the right hand core leg. The remaining end sheets alternate in the same way until the core is completely assembled.

In practice, as shown in the drawings, the units of assemblage comprise two or more single laminae.

Reference to Fig. 6 is again necessary in order to explain how from the two different kinds of U-shaped laminae shown in Fig. 5 the result shown in Fig. 5 is accomplished by means of the alternating guides I-and G.

Beginning at the bottom of Fig. 6, a group of two laminae O is laid with its short leg 0 in the foreground and its long leg 0, with the background. The fourth layer consists of a group of two of the laminae O, which form the first layer, but turned upside down, so that their long legs 0 and outer cut-away cornerI are in'the foreground and their short legs 0 are in the background. This series operator can quickly and accurately insert the ends E in the proper position after the coils have been slipped over the core-legs.

Fig. 8, which is an end view of that portion of the core in which the end laminae E are inserted, shows the method of locking the end laminae in position. The strip K has its ends interlapped with the legs of the U- shaped laminae, so that the adjacent end sheets, which would otherwise be free, are not permitted to flare out beyond the core-legs.

hat I claim as new, and desire to secure by Letters Patent of the United States, is 1. A laminated transformer-core which has two legs, each having the same number of laminae; which comprises a plurality of substantially U-shaped laminae, each of whichhas a long and a short leg; and also a plurality of end laminae for completing the magnetic circuit; said core being built up so that the long and short legs of the U -shaped laminae alternate in the respective core-legs; and the end laminae, the two coils being in position on the core-legs, being also alternated so that one end of one lamina fills the space at the end of a short leg of a U-lamina of the first core-leg, the other end of said end lamina abuts against the long leg of the same U-lamina in the second core-leg, one end of the next end lamina fills the space at the end of the short leg of the next U-lamina in the second core-leg, and so that the other end of the latter end lamina abuts against the long leg of the latter U-lamina in the first coreleg.

2. A transformer-core, which comprises a plurality of substantially U-shaped laminae, each of which has along and a short leg; said laminae being assembled alternately to form two core-legs of the same thickness and the same number of laminae; and end laminae which complete the magnetic circuit.

3. Alaminatedtransformer'core,whichhas two legs each having the same number of laminae and which comprises a plurality of substantially U-shapedlaminae,each of which has a long and a short leg, said laminae being alternately reversed, so that each short leg is included between two long legs; and end laminae which complete the magnetic circuit.

a. Alaminatedtransformer-core,whichhas two legs each having the same number of laminae, and which comprises a plurality of U-shaped laminae, each of which has a long and a short leg, said laminae being alternately reversed so that a short leg lies between two long legs and a long leg lies between two short legs, and laminae having a width substantially equal to the dilference between the lengths of the long and short legs, one set of ends of which laminae fill the spaces in one core-leg between the long legs which lie on opposite sides of the short leg, and the other set of ends of which laminae abut against the sides of the long legs of the other core-leg.

5. A transformer-core, which comprises a plurality of substantially U-shaped laminae,

each of which has a long leg and a short leg, said laminae being alternately reversed, so that each short leg is included between two long legs; and end laminae which alternate to fillthe spaces between the long legs at the ends of the short legs and serve to complete the magnetic circuit.

6. A transformer-core, which comprises a plurality of substantially U-shaped laminae, each of which has a long and a short leg, certain of the laminae having the inner corners of the long legs cut away, certain others of the laminae having the outer corner of the long legs cut away, and a core being built up first, with one or more laminae of one kind, next, laminae of the other kind, then laminae of thelatter kind turn ed upside down, fourth, laminae of the first kind turned upside down and so on until the core is complete; and end laminae for completing the magnetic circuit, which laminae are inserted between the long legs of the U-shaped laminae as indicated by the cut-away corners.

7. A transformer-core, which is built of a plurality of substantially U-shaped laminae, each of which has a long and a short leg, each built-up core-leg being composed of long and short legs alternately arranged, all the long legs in both core-legs having guides at their ends which serve to indicate the proper spaces for the insertion of end laminae.

8. A transformer-core, which is built up of a plurality of substantially U -shaped laminae, of two kinds, both kinds of which have long and short legs, one of which kinds has the inner corners of the ends of the long legs cut away, the other of which kinds has the outer corner of the ends of the long legs cut away; and each leg of the core being composed of long and short legs alternately arranged, the two long legs which include a short leg belonging respectively to the said two kinds of laminae.

9. A transformer-core, which is built up of a plurality of substantially U shaped laminae of two kinds, both of which kinds have long and short legs, one of which kinds has char acteristic guides at the ends of the long legs, and the other of which kinds has difierent characteristic guides at the ends of its long legs; each leg of the core being composed of long and short legs alternately arranged, and the two long legs which include a short leg be longing respectively to the two kinds of laminae.

10. A transformer-core, which comprises a plurality of substantially U-shaped laminae, each of which has a long and short leg, certain of the laminae having the outer corner of the long leg cut away,'certain other of the laminae having the inner corner of the long leg cut away, and the core being built up, first, with one ormore laminae having an outer corner of the long leg cut away, second, with laminae having the inner corner of the long leg cut away, said long leg lying in the other leg of the core with respect to the first long leg; third, with laminae having the inner corner of the long leg cut away, but turned upside down so that the long leg lies in the same core-leg as the long leg of the first laminae; and fourth, with laminae-having the outer corner of the long legs cut away, but turned upside down so that the long leg lies in the same core-leg as the long legs of the second laminae; fifth, with laminae like the first, and so on, until the core is complete, and end laminae for completing the magnetic circuit, which laminae are inserted between the ends of the long legs of the laminae of one core-leg and abut against the edges of the ends of the long legs on the other core-legs, and vice versa, according as indicated by the cut-away corners of the long legs.

11. A plurality of substantially U-shaped laminae each having a distance between its legs equal to twice the width of a leg, said laminae being assembled in reverse order so that a short leg is included between two long legs, and vice versa, in combination with separate end laminae for completing the magnetic circuit and filling the spaces at the end of the short legs between the long legs.

12. A substantially U-shaped lamina having a long and a short leg, the difierence between the lengths of the legs being substantially one-half the distance between them.

13. A transformer-core, which comprises a 14:. A substantially U-shaped lamina, hav

ing a long leg and a short leg, the difierenee between the lengths of said legs being substantially equal to the width of the base of the lamina, and substantially equal to onehalf the distance between the legs.

15. A transformer-core, which comprises a plurality of substantially U-shaped laminae, each having a long and a short leg, the difference between the lengths of the legs being equal to the width of the base of the laminae, and to one-half the distance between the legs, and end laminw for completing the magnetic circuit, the widths of which end laminae are equal to the difierence between the lengths of the long and the short legs of the U -shaped laminae.

In witness whereof I have hereunto set my hand this 1st day of March, 1901.

AUGUSTINE R. EVEREST. Witnesses:

DUGALD McK. MCKILLOP, JOHN J. WALKER. 

